Reducing river pollution

RDPE helps to reduce pollution in Devon’s River Avon

At the mouth of the river Avon in south Devon, oyster farmer
Richard Marsh and his father Peter harvest 20 tonnes of oysters a
year. However, a few years ago it was a different story. The farm
was facing several closures a year because of high levels of e-coli
in the oyster flesh, indicating that faecal matter was present in
the water system, with a subsequent risk of food poisoning to
humans. In order to address the problem it was necessary to
identify where the pollution was coming from. Possibilities in the
River Avon included poorly treated water at a sewage works, as
farmers claimed, or farmers’ fields, as the sewage works
claimed.

The England Catchment Sensitive Farming Delivery Initiative
(ECSFDI) – a programme funded through the RDPE and run jointly
by the Environment Agency and Natural England – works in 50
priority catchments across the country using a voluntary approach
to enable farmers to reduce their impacts on sensitive water
resources. Lizbe Pilbeam who works on the Initiative in the region
said: “I decided we needed to have the scientific evidence to show
where the e-coli was coming from. I contracted microbiologists to
analyse the DNA in water column samples and shellfish flesh from
the estuary in order to clarify whether the source of the e-coli
was from humans or livestock.”

Lizbe expected the testing to show that both sources were
responsible for the pollution, but was amazed when the results
showed that around 98 per cent of the e-coli was from livestock.
She said: “When I took this evidence back to the farmers they were
absolutely fantastic and really took ownership of the issue.” The
pollution levels were worst where cattle had direct access to
streams and could defecate directly into the water. Cattle were
spending hours in the water particularly in hot weather when a
stream offers a cool, shady and fly-free spot. Dung would then flow
untreated into the Avon and directly through areas like Richard
Marsh’s oyster farm, or into bathing waters.

The solution was a simple one; to fence off the streams so that
the cattle couldn’t get to them. The ECSFDI provided grants which
covered half of the costs and farmers covered the remaining expense
themselves. “If you’ve ever seen anyone with e-coli poisoning, you
know why we’ve had to fence streams out,” says local dairy farmer
John Tucker. “No one could then put the blame on the farmer because
he’s done his bit.”

The results for the oyster farm were instantaneous. “As soon as
they fenced off the streams the e-coli levels went down,” said
Peter Marsh. “There was one occasion when there was a sudden spike
in the charts and we found that the cattle had broken down the
fence and were back in the stream, so the link is that clear.” Now,
the oyster farm doesn’t face any closures due to high e-coli levels
and the Food Standards Agency has even upgraded the quality of
water in one of its oyster beds from C to B classification under
the Food Hygiene Regulations. Peter continued: “Oyster farming is a
very marginal business so the scheme has made a massive difference.
The whole community is involved, from farmers to bathers to us.
Everyone’s more conscious of the problem and has contributed to
solving it.”

Over the past four years, the ECSFDI in south Devon has given
out more than £700,000 in grants for fencing, water troughs and
pumping systems to supply the cows with a new water source. Lizbe
said; “Although farmers have put up over 60km of new fencing with
grant support to help install it, they are the ones who have to
maintain it. They’ve really taken responsibility for the problem
and the positive effects are huge.”